C
OMMAND
L
INE
I
NTERFACE
4-102
Default Setting
Status: Disabled
Action: None
Maximum Addresses: 0
Command Mode
Interface Configuration (Ethernet)
Command Usage
• If you enable port security, the sw itch will stop dynamically learning
new addresses on the specified port. Only incoming traffic with source
addresses already stored in the dynamic or static address table will be
accepted.
• To use port security, first allow th e switch to dynamically learn the
<source MAC address, VLAN> pair for fram es received on a port for
an initial training period, and then enable port security to stop address
learning. Be sure you enable the learning function long enough to
ensure that all valid VLAN members have been registered on the
selected port.
• To add new VLAN members at a later time, you can manually add
secure addresses with the mac-address-table static command, or turn
off port
security to re-enable the learning function long enough for new
VLAN members
to be registered. Learning may then be disabled again,
if desired, for security.
• A secure port has the following restrictions:
- Cannot use port monitoring.
- Cannot be a multi-VLAN port.
- Cannot be connected to a network interconnection device.
- Cannot be a trunk port.
• If a port is disabled due to a security violatio n, it must be manually
re-enabled using the no shutdown command.